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991.
The efficiency of short-segment fixation with transpedicle body augmenter (a titanium spacer with bone-ingrowth porous surface, TpBA) to treat Kümmell's disease with cord compression (stage III) was retrospectively evaluated. No laminectomy or instrumentation reduction was done. Inclusion criteria included Frankel CDE, single-level within T10-L2. FU rate was 88%, i.e. 21 cases were included. Frankel function classification was 6E9D6C. Mean age was 72+/-8 years. F:M was 16:5. FU period was 48 M (range, 30-76 M). The hospitalization was 4.5+/-2.2 days; operation time, 70.4+/-17.2 min; blood loss, 150+/-72 cc. Final Frankel class was 20E1D. Complications included two superficial infection and one pneumonia. Body height and kyphosis were all corrected significantly and well preserved at the final visit. No TpBA dislodgement or implant failure was noted; however, three cases developed new compression fractures. The clinical outcome showed 81% with P1 or P2 by Denis pain scale. This method can decompress spinal canal, maintain kyphosis correction and vertebral restoration, prevent implant failure, and attain good clinical results.  相似文献   
992.
To investigate the role of hepatitis B (HBV) and C viruses (HCV) in hepatocellular carcinoma (HCC) in an HBV endemic area and elucidate the interaction of these two viruses, a case-control study of 128 patients with HCC and 384 age-matched and sex-matched control subjects was done. The positive rates of hepatitis B surface antigen (HBsAg, 77.3%, 99 of 128) and anti-HCV (19.5%, 25 of 128) in patients with HCC were significantly higher than in control subjects (P less than 0.001). Both HBsAg and anti-HCV were important risk factors for HCC (relative risks, 13.96 and 27.12, respectively), and the risk for HCC was elevated significantly to 40.05 (95% confidence interval, 12.57 to 127.6) when HBsAg and anti-HCV were considered simultaneously. These results suggested that HBV and HCV were associated highly with HCC in an HBV endemic area and that these two viruses might contribute independent but synergistic effects to the pathogenesis of HCC.  相似文献   
993.
Combined heart-lung transplantation has been used for end-stage primary pulmonary hypertension. Experience with single-lung transplantation for other conditions suggested that associated severe right ventricular dysfunction resulting from increased afterload would recover after placement of a satisfactory lung allograft. Early experience with the application of single-lung transplantation for pulmonary hypertension supports this contention. We devised a reversible canine model of chronic progressive pressure-overloaded right heart failure by pulmonary artery banding to study the echocardiographic, hemodynamic, and pathological reversibility of the failing right heart. Clinical right heart failure was defined as the development of ascites and pleural effusions. Right heart failure developed in 23 dogs 67 to 348 days after banding, and they were divided into two groups to determine its early and long-term effects. Group 1 dogs (n = 11) were either sacrificed immediately after the onset of right heart failure (n = 5) or unbanded (n = 6); group 2 dogs (n = 12) were maintained in right heart failure for 3 months and then either sacrificed (n = 6) or unbanded. Unbanded dogs in both groups were observed for 4 additional months before sacrifice. A control group of 6 normal dogs was sacrificed for pathological comparisons. After unbanding, the right ventricular systolic pressure fell from 97 +/- 17 mm Hg (group 1) and 88 +/- 31 mm Hg (group 2) to 44 +/- 11 mm Hg and 47 +/- 13 mm Hg, respectively. Despite this persistent gradient across the pulmonary artery, echocardiographic and hemodynamic measures of right ventricular function returned to normal, albeit more slowly in the group 2 dogs.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
It is frequently assumed that the risk of hepatocellular carcinoma related to hepatitis B virus is higher when chronic hepatitis B virus infection is acquired early in life. This hypothesis has never been directly evaluated. However, firstborn and secondborn children are exposed to common infections after their school enrollment, whereas laterborn children are exposed much earlier, through their older siblings. The authors analyzed sibship size and birth order data from a large case-control study of patients admitted to Athens, Greece, hospitals between April 1976 and October 1984. The analyses included 185 patients with hepatocellular carcinoma, 35 patients with metastatic liver cancer, and 432 other hospital controls. There was a tendency for cases of hepatocellular carcinoma to concentrate at higher birth orders. When the analysis was restricted to cases and controls who were positive for hepatitis B surface antigen, this tendency was even more notable. These results are compatible with the hypothesis that establishment of chronic hepatitis B virus infection at an early age increases the risk of hepatocellular carcinoma substantially more than does chronic infection with this virus established at a later age.  相似文献   
995.
Enantioselectivity of esterases, contained in 9,000g supernatant fraction (S9) prepared from homogenate of small intestinal mucosa of male Sprague-Dawley rats and the subsequent 105,000g supernatant (cytosol) and pellet (microsomes) prepared from S9, was studied using racemic oxazepam 3-acetate (rac-OXA) as the substrate. Esterases in S9 were enantioselective in hydrolyzing either S-OXA or R-OXA, depending on a particular subcellular preparation. Cytosolic and microsomal esterases had opposite enantioselectivity and selectively hydrolyzed S-OXA and R-OXA, respectively. Enantioselectivity of esterases solubilized from microsomes with Triton X-100 (0.1%, w/v) was identical to that of the membrane-bound microsomal esterases. Cytosolic esterases were more sensitive to temperature than either solubilized or membrane-bound microsomal esterases. In the presence of paraoxon (1 microM), the esterases selective toward R-OXA in both microsomes and S9 were completely inhibited, whereas the esterases selective toward S-OXA in cytosol were inhibited by approximately 6%. These results indicate that cytosolic and microsomal esterases in rat small intestinal mucosa are distinctly different enzymes, with opposite enantioselectivity in the hydrolysis of rac-OXA.  相似文献   
996.
D H Livingston  M T Wang  J Hsieh  T F Murphy  B F Rush 《Surgery》1992,112(4):773-9; discussion 779-80
BACKGROUND. Bacterial translocation has been implicated in the alteration of the immune response after shock and trauma. This study examined the effect of bacterial translocation on myelopoiesis after hemorrhagic shock in germ-free and conventional rats. METHODS. Awake, unrestrained germ-free and conventional rats were bled to a mean arterial pressure of 30 mm Hg until the animal required infusion of 10% of the shed blood. Rats were resuscitated with shed blood and crystalloid. Sham rats were catheterized but not bled. Twenty-four hours after shock or sham, rats were administered lipopolysaccharide 100 micrograms or saline intraperitoneally. Twenty-four hours later, bone marrow cells were cultured for growth of granulocyte-macrophage colony-stimulating factor (CFU-GM). RESULTS. Lipopolysaccharide increased the number of CFU-GM/femur in sham germ-free rats (801 +/- 129 versus 455 +/- 110; p less than 0.05) and conventional rats (1458 +/- 200 versus 492 +/- 59; p less than 0.05) compared with saline-treated rats. In contrast, hemorrhagic shock inhibited lipopolysaccharide-induced CFU-GM growth in both germ-free and conventional rats. Shock, itself, was a stimulus for CFU-GM growth in germ-free but not conventional rats. Bone marrow white blood cell counts were unaffected by shock, lipopolysaccharide administration, or the germ-free state. CONCLUSIONS. Hemorrhagic shock inhibited lipopolysaccharide-induced CFU-GM proliferation independent of the germ-bearing status of the rat, and bacterial translocation exerted no influence on myelopoietic dysfunction after hemorrhagic shock.  相似文献   
997.
998.
Rhenium-188 is extremely suitable for the radiotherapy of balloon dilation for the coronary artery restenosis. To satisfy the need of highly concentrated (188)Re-perrhenate for the clinical applications, we designed an apparatus to achieve the purpose of concentrating (188)Re-perrhenate solution. This apparatus comprised of a concentrator, a control box and a computer with an automatic control program. A column of cation-exchange resin in Ag(+) form and an anion-exchange column in series were used in the concentration procedure. More than 90% of (188)Re isotope in the original solution could be collected with 1mL of 0.9% NaCl solution added to collect the (188)Re adsorbed in the column in this final process (90.7+/-2.2%, n=15). We also found that the radiochemical purity in the final solution remained unchanged (100%). The designed process could automatically increase the quality and efficiency of the production of highly concentrated rhenium-188 solution, and could also reduce the radiation dose absorbed by the operator.  相似文献   
999.
1000.
J L Yang  Y C Hsieh  C W Wu  T C Lee 《Carcinogenesis》1992,13(11):2053-2057
Chromium(VI) compounds exert their genotoxicity and mutagenicity by complex metabolic reducing pathways that generate a variety of reactive forms of chromium and free radicals. To investigate the molecular nature of chromium-induced mutations, we characterized the entire coding region of the hypoxanthine (guanine) phosphoribosyltransferase (hprt) gene of 27 independent mutants derived from chromium(VI) oxide (CrO3)-treated Chinese hamster ovary-K1 cells, by direct sequencing of PCR-amplified cDNA. Among these mutants, 10 consisted of single base substitutions, five contained two base substitutions, one had four base substitutions, six were splicing mutations, and five exhibited single base pair insertions or deletions. All of the base substitutions and most of the frameshift mutations observed were located at A/T-rich sequences. More than 90% of the base substitutions (22/24) occurred in A.T base pairs. Among them, T-->A and T-->G transversions (18/22) predominated. The mutational hotspots for single and double base substitutions were the 3' thymidine of 5'PuT and thymidines of 5'ATTT sequences respectively. This mutational specificity was also observed in CHO-K1 cells treated with two other chromium(VI) compounds, namely K2Cr2O7 and PbCrO4. Strand bias was noticed in chromium mutagenicity, since 77% of T base substitutions occurred on the non-transcribed strand. This highly sequence-specific mutation spectrum suggests that a particular form of chromium may directly interact with DNA at these hotspot sequences.  相似文献   
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